I have a database that tracks job expenses through change orders. This is done in a portal. I want a layout that details by vendor the total of change orders across all jobs. So for example, for vendor X I want a layout that has all of the change order 1 costs, the totals for change order 2 for each job etc. I'm having trouble referring to the data that is beyond the first line of the portal as that is what filemaker sees when I relate to it.
What I'm picturing from your post is that you have a portal and you want a total of all the values listed in the portal. Right?
If so, define a calculation field:
PortalTableName should be the name of the Table Occurrence you specified when you set up the portal. NumberField is the name of the field listed in the portal that you want a total value for.